Method of reinforcing paper boxes.



APPLIOATION IIIQED OCT. 22

Patented Apr. 9, 1912.

Mama

' UNITED STATES PATENT OFFI ES CHARLES s; BIRD, or EAST WALPOLE, massecnusnr'rs.

METHOD OF REINFORCILIG PAPER BOXIlS.

Specification of Letters Patent.

Patented Apr. 9, 1912.

Application filed October 22, 1910. Serial No. 588,402.

To all whom it may concern:

Be it known that I, CHARLES- S. BIRD, a

citizen of the United States, and a resident of East Walpole, in the county of Norfolk and State of Massachusetts, have invented v certain new and useful Improvements in the Methods of Reinforcing Paper Boxes, of which the following is a specification, reference being had to the accompanying drawmgs.

This invention relates to the manufacture of folding paper boxes or box covers, and especially to that class of paper boxes in which strawboard blanks are creased,

scored and bent into position, the object be ing to provide a box or cover which shall have all the strength, rigidity and-stability of a set-up box.

In order that the strawboardblanks may be bent into proper position, it is necessary to crease or score the same so that the bend may be made in accordance with the lines of crease or scoring. Such creasing or scoring necessarily presses into the body of the strawboard and tends to deprive it of its strength and stability along said creases which are to be the edges and corners of the paper box and are peculiarly liable to rough handling and Wear.

Heretofore the method of strengthening or reinforcing such edges and corners has v depended wholly on a stay-strip pasted on the outside or inside of the box, after the box has been set up in position and ready to be used. Inasmuch as the strawboard has been weakened materiall by the creasing and bending, which is 1i rely to cause cracks, the strength of the finished folding paper box depends largely on the strength of the'staystrip or reinforcing strip, such stay-strips or reinforcing strips being applied either on the inside or outside of the box proper.

The object of my invention is to prevent the strawboard from cracking along the lines of crease when the same is bent into position for use in a paper box, and to this end the present invention involves the method of applying reinforcing strips along the lines of crease on the inside of the box before such crease 'or' scoring is made and thereafter creasing or scormg as 1s desired and then forming the box blank into the sides and ends of the box or cover. The reinforcin strips may also be applied to the 56 strawboar after the'creasing or scoring has been accomplished, the primary object being to have the strips applied to thestrawboard along the lines of creasing and bending before such bend is made.

In the accompanying drawings, Figure 1 is a. perspective View of a box blank creased and bent with its flaps and sides ready to the sides and ends of any folding paper box blank.

B are the flaps integral with A and adapted to be bent at right angles to form the sides and ends of the box.

C is a reinforcing strip or sheet of paper or cloth of such size asto be pasted along the line of creasing or scoring in such manner as to lap over onto the strawboard material on either 'side of the line of creasing or scoring, as shown in Figs. 1 and 3.

D represents the indentation upon the strawboard made by the creasing or scoring machine along the line where such strawboard is to be bent into position.

E represents the bulging of the material and reinforcing strip C formed by the creaslng.

One of the methods of applying my invention is as follows: The strawboard blank from which the paper box or cover. is to be formed is covered on the lines of pros ective creasings and scorings with the rein orcing strips or sheets of paper or cloth G, by means of paste or other suitable material, the paper box blank being now as is shown .in Fig. 2. The blank is then passed through the creasing or scoring machine, which indents at D the crease, so thatthe blank has the appearance along the creased lines as is shown in Fig. 3. It will be noted that the reinforcing strip 0 prevents the cutting or.

tearing of the strawboard on the inside during this roces's. The reinforcing strip C may also e applied to the strawboard after the blank has been creased or scored and the same effect is thereby produced. Now when the box blank is ready to be formed into the box proper so that the parts on either side of the creasing and scoring lines are bent into position substantially at right angles to each other the material of the strawboard and the crease will assume the positions shown in Fig. 4,: the various strata of the strawboard not being torn or broken owing to the reinforcing strip having been first pasted on prior to the bending of the box and the indentation formed by the creasing or scoring on the outside at D making a smooth and rounded corner for the angle edge or corner of the box. It will be seen therefore that the ordinary box, cartons and crates may be made of great strength and rigidity when my method of reinforcing the blanks is adopted, for the material is not only prevented from cracking and tearing along the line of crease, butin addition thereto there is combined the added strength of the interior reinforcing strips.

\Vhat I claim as new and desire to secure by Letters Patent is the following, viz

1. The method of reinforcing rectangular folding paper boxes composed of friable material, which consists first in pasting on the inner surface of the friable box blank along the prospective lines of creases comparatively thin reinforcing strips while said box blank is still flat, second, simultaneously creasing both the said friable blank and the said thin reinforcing strips without disintegrating the component layers of said blank and said strips so as to form a concavo-convex crease projecting on the inner surface of said box blank, and finally folding the blank into-final position to form the rectangular box without tearing or cracking the layers of the blank and having said reinforcing strips on the inner surface of the rectangular folding box, substantially as described.

2. The method of reinforcing a rectangular folding box composed of friable material, which consists first in pasting on the inner surface of the friable box blank along the prospective lines of creases comparatively thin reinforcing strips While said box blank is still fiat, second, simultaneously creasing both the said friable blank and the said thin reinforcing strips without disintegrating the component layers of said blank and said strips so as to form a concave crease on the side of the box blank opposite said strips, and finally folding the blank into final position to form a rectangular box without tearing or cracking the layers of the blank and having said reinforcing strips on the inner surface of the rectangular folding box, substantially as described.

3. The method of reinforcing angular folding paper boxes composed of friable material which comprises first pasting onto one surface of the still flattened blank along the prospective lines of creases, strips of comparatively thin reinforcing material, next simultaneously creasing in one and the same direction both the so combined materials, and finally simultaneously bending them in one and the same direction to the angle of fold required by the finished box.

CHARLES S. BIRD.

Witnesses:

R. L. TUPPER, P. R. ALLEN. 

